Rapid changes and increases in demand for telecommunication services increase the pressures for cost effective engineering and upgrading of the telephone network. The demand for traditional telephone service continues to increase, but at a steady and readily predictable pace. Several newer types of traffic through the telephone network, however, are increasing at an exponential rate and impose new traffic patterns that exacerbate difficulties in meeting the new traffic demands. The most significant and burdensome of these new types of traffic relates to calls through the telephone network to access data services, particularly the Internet.
The most common form of Internet access relies on modems and analog telephone network connections. A modem of this type modulates data from a personal computer (PC) for transmission in the voice telephone band over a telephone connection to the Internet service provider (ISP) and demodulates data signals received from the ISP over such a link. The analog telephone modem operates at one subscriber premises end of a voice grade line to transmit and receive signals over the line and through the telephone switch network to and from another similar line and modem in communication with an ISP's host equipment.
To access the Internet, the user activates her PC and modem to dial a number for the ISP. The telephone network switches the call through to a line going to a modem pool operated by the ISP. Once connected through the telephone network, the user logs on, and the ISP's equipment provides communications over the worldwide packet switched network now commonly known as the Internet. This telephone-based operation provides the voice grade analog modem a unique power, the necessary connections for Internet access are virtually ubiquitous. Users can call in from virtually any telephone line or wireless telephone (e.g. cellular) almost anywhere in the world.
However, the calling patterns for this type of data communications, particularly Internet access, are radically different from those of normal voice traffic. The sudden increase in popularity of access to the Internet and the difference in call-in traffic patterns have radically changed the loading placed on the telephone network.
Normal voice telephone calls tend to occur at random times, and the network typically routes the majority of such calls to random destinations. Also, the average hold times for such calls tend to be short, e.g. three minutes or less. By contrast, Internet traffic tends to have severe peak traffic times during any given twenty-four hour period, e.g. from 8:00PM to 11:00PM. Also, the network must route Internet access calls to a very small number of destinations, i.e. to the lines for modem pools operated by Internet Service Providers (ISPs). Instead of many parties calling each other randomly, many callers are all calling in to a limited number of service providers. Finally, hold times for Internet calls can last for hours. Some Internet users access the Internet when they sit down at their desks and leave the call connections up until they decide to turn their computers off, e.g. at the end of their day. If they leave their computers on all the time, the connections to the ISPs may stay up for days. These Internet traffic patterns add incredibly heavy traffic loads to the telephone network and tend to concentrate those loads in specific offices providing service to the ISPs.
The local exchange carriers (LECs) are considering a number of different options for relieving the congestion caused by Internet access traffic. Using existing technologies, these options include deploying more switches and trunk circuits and designing the connections of switches and trunks to the ISPs and their high-end users to minimize call switching and/or trunk congestion. For example, if there is a heavy concentration of ISP bound calls from a mid-town end office switch to an end office in the suburbs that serves the ISP, the LEC might install additional direct trunks between those offices to reduce the need for overflow routing through a tandem office. Within the mid-town office switch, the LEC might connect the high-end users that call the particular ISP to the same switch module that connects to the new direct trunks to the suburban end office, in order to reduce the inter-module switching load within the mid-town switch. Similarly, in the suburban office, the LEC would connect the new trunks to the same switch module that serves the ISP.
The carriers also are considering and experimenting with a number of options to off-load the Internet access traffic from the voice telephone network. Such options range from deployment of dedicated trunks to the modem pools of the ISPs to deployment of advanced digital loop carrier systems that can recognize data calls and switch such calls over to some link directly to a fast packet network. Other technologies, such as Asynchronous Digital Subscriber Line (ADSL) networks, provide a totally separate logical path for the data communications.
The various strategies intended to address the increasing traffic demands of Internet access, such as adding end offices, deploying specialized switching modules, installing ADSL networks, adding trunks, deploying more tandem offices and the like, all require considerable expense by the carriers. Accurate engineering, to minimize cost and yet reduce congestion and provide effective service to the various customers, becomes ever more essential. To provide effective engineering, it is necessary that the carrier understand the traffic involved. Such understanding requires accurate and complete traffic measurement. Accurate information also is necessary to resolve disputes, for example with the ISPs over service quality.
Understanding the loading caused by access calls to ISPs requires identifying the high-volume users of data services. Identifying such users would allow network engineers to design off-load strategies to reduce congestion. Such knowledge also would enable the carrier to focus efforts to market advanced data services, such as Asynchronous Digital Subscriber Line (ADSL), to customers having an existing need for data services. These often are the customers most troubled by network congestion and low-bandwidth. As discussed more later, current technology does not readily enable identification of heavy callers to data services or the like.
A need therefore exists for an effective technique to measure and analyze unique traffic patterns, particularly as they relate to Internet access calls. A more specific need is for a technique to measure traffic, identify characteristic traffic patterns and determine therefrom the heavy users making calls to the data access points, e.g. the heavy callers to the ISPs.
A number of techniques have been developed for monitoring operations of the public switching telephone network. While these prior techniques may be effective for some purposes, they have not proven effective for analyzing Internet access traffic or recognizing heavy users of data services. To complete the understanding of the background of the invention, it may be helpful to briefly consider some of the prior techniques for network monitoring.
U.S. Pat. No. 5,475,732 Pester describes an SS7 Network Preventative Maintenance System for detecting potential SS7 and switched network troubles, automatically analyzing the troubles, and providing alarm and corrective action to avoid major network events. The Pester SS7 Real Time Monitor System described in that Patent is a multi-stage SS7 network preventative maintenance tool that traps SS7 messages, detects potential SS7 and switched network troubles, automatically analyzes those troubles, and provides alarm and corrective action instructions to maintenance personnel
U.S. Pat. No. 5,592,530 to Brockman et al. relates to an SS7 monitoring system for evaluating the operations of telephone switches by capturing data between signaling nodes of a telephone switching system. The Brockman et al. surveillance equipment captures signaling information from different signaling network paths within a mated STP pair and correlates the fragmented messages for each monitored call. The system is capable of generating call detail records from the SS7 messages of a mated pair cluster, for use in billing and fraud detection.
While the above discussed Pester and Brockman et al. Patents describe the usefulness of monitoring an SS7 common channel interoffice signaling network for event detection, neither of these patents is directed to the particular problems of traffic measurement addressed by the present invention. The Pester Patent places emphasis on monitoring of the SS7 network itself in order to detect troubles in its functioning. The Brockman et al. Patent focuses on monitoring of all links to the STPs in a pair and the assembly of related SS7 signaling messages to form a record of call completions.
While these methodologies may be effective for their stated purposes there remains a distinct need for an efficient and effective tool for monitoring and analyzing types of traffic through the telephone network, to recognize unique patterns and identify key users involved in such traffic patterns. Attempts to use other more traditional approaches, such as the accumulation of data from the switches themselves and the Engineering and Administrative Data Acquisition System fell short of providing the desired information.
For example, today, a LEC conducts studies on usage in an office by setting up a “busy study” with respect to specific individual lines served through that office. It is not possible to look at all the traffic in the office at one time. Typically, the LEC can study maybe three different lines at a time. So in a 50,000-line office the LEC engineers can examine the traffic for up to three hundred lines at any one time. Also, setting up and maintaining such studies are labor intensive. To conduct a meaningful number of studies throughout a large service area, a LEC virtually needs an army of clerical people whose main job function is setting up busy studies. Once set up, such a study may run for three weeks, but at the end of that time, it takes another two weeks to process the output and organize the results into a report. Results are not available in real-time. Even when results do become available, the study only shows data on a few lines that may or may not be causing blockage in the busy hour. If the lines were not properly selected, the busy study may be virtually meaningless to the network engineer trying to relieve congestion through the office. Traffic patterns are changing rapidly, e.g. as new ISPs obtain lines or existing ISPs add new lines in already congested service areas. As a result, by the time that the engineer accumulates enough data for a meaningful study, the data may already be obsolete. Finally, the known network study techniques provide little or no help identifying the high volume users; i.e. the users who call often and exhibit long hold times on the calls to the service provider.
It is accordingly an object of this invention to provide a relatively low cost solution to those problems.
It is another object of the invention to provide a timely, powerful, cost effective means of analyzing traffic on the Public Switching Telephone Network (PSTN) to identify the calling parties involved in unique and troublesome traffic patterns.
It is a further object of the invention to provide a flexible, expedient, accurate, and cost effective method to identify individual calling parties (numbers and/or lines) contributing to network blockage. Specifically, it is an object of the invention to provide such a technique to identify numbers or lines associated with high volume Internet users.
It is yet another object of the invention to implement Internet related traffic studies and enable better service to Internet users while maintaining optimal network utilization.